The present invention is related to inventions disclosed in copending applications Ser. No. 894,479, filed Apr. 7, 1978, now abandoned, and Ser. No. 800,747, filed May 26, 1977, now abandoned, U.S. Pat. No. Re. 29,022, U.S. Pat. No. 4,113,180 and U.S. Pat. No. 3,954,223, and is summarized in the following objects:
First, to provide an irrigation emitter involving an emitter element enclosed in a housing arranged for attachment to a flow line which can be manufactured and assembled at minimal cost.
Second, to provide an irrigation emitter including a housing forming a chamber wherein perforated inlet and outlet walls diverge diametrically from a common apex which retains an end of an elastomeric emitter plate that is angularly movable between contact with the inlet and outlet walls to form with the outlet wall at a predetermined low pressure, a flush flow passage, the emitter plate and outlet wall defining therebetween drip flow passage operable above the flush flow pressure.
Third, to provide an irrigation emitter, as defined in the other objects, in which the housing may include an inlet in coaxial relation with the outlet and the emitter disk may close or nearly close the inlet between irrigation cycles, whereby, on initiation of an irrigation cycle, a slight delay in flush flow occurs to permit an increase in the line supply tube pressure exposed to the inlet; thus increasing the rate of movement of the emitter disk toward drip flow and increasing the number of emitters which may be used on a supply line.
Fourth, to provide an irrigation emitter, as defined in the other objects, wherein the material forming the emitter disk is yieldable to an increase in water pressure to effect a corresponding decrease in the area of the drip channel, thereby to cause approximately uniform drip flow over a range of water pressures.
Fifth, to provide an irrigation emitter, as defined in the other objects, wherein the emitter disk is provided at the discharge end of the drip passage with a deflector to maintain a slow velocity discharge.